Niall Horan gatecrashed a 5 Seconds of Summer interview.

The One Direction star decided to interrupt an interview with 5SOS's Michael Clifford and Luke Hemmings during a backstage interview at the American Music Awards.

The 22-year-old heartthrob stormed in on 5SOS post performance interview with Sugarscape and said: ''I just thought I'd come say hello.''

Luke, 19, remarked: ''You look a little drunk''.

The 'Drag Me Down' singer then asked the 5SOS boys: ''Are you drinking without me boys? Can you not wait?''

5SOS previously supported One Direction - which also includes Harry Styles, Liam Payne and Louis Tomlinson - on their 'Take Me Home' tour in 2013 and it was clear that the bond had not been lost.

Niall said: ''It was Mikey's birthday the other day. We all hung out. We all love each other.''

Mikey - who had recently celebrated his 20th birthday - added: ''We all touched butts.''

While Luke shared: ''We had some intimate moments.''

Niall then left the boys to complete the interview and got ready for One Direction's rendition of 'Perfect'.